What are the indications for activation of Massive Transfusion Protocol (MTP)?

From the Guidelines

Massive Transfusion Protocol (MTP) should be activated in patients with severe hemorrhage who are anticipated to require large-volume blood replacement, particularly those with major trauma, hemodynamic instability, or ongoing class III or IV hemorrhagic shock, as evidenced by the recent European guideline on management of major bleeding and coagulopathy following trauma: sixth edition 1.

Indications for MTP Activation

The primary indications for MTP activation include:

• Patients who have received or are expected to need more than 4-6 units of packed red blood cells within a 4-hour period
• Patients who have lost or are expected to lose more than 40% of their blood volume
• Specific clinical scenarios such as major trauma with hemodynamic instability, ongoing class III or IV hemorrhagic shock, penetrating torso injuries with active bleeding, multiple amputations, severe gastrointestinal bleeding, ruptured aortic aneurysm, obstetric hemorrhage, and major surgical bleeding ### Assessment Tools Assessment tools like the Assessment of Blood Consumption (ABC) score or Shock Index (heart rate divided by systolic blood pressure >1.0) can help identify patients who may benefit from MTP 1.

Blood Product Ratio

Once activated, MTP typically delivers blood products in a balanced ratio of packed red blood cells, fresh frozen plasma, and platelets, often 1:1:1, to prevent both hemorrhage and coagulopathy 1.

Early Administration of Tranexamic Acid

Early administration of tranexamic acid (1g IV over 10 minutes, followed by 1g over 8 hours) is also recommended within 3 hours of injury 1.

Rationale

The rationale behind MTP is to address the consumption of clotting factors and platelets that occurs with massive hemorrhage, creating a vicious cycle of bleeding and coagulopathy that standard replacement strategies cannot address effectively 1.

From the Research

Indications for Activation of Massive Transfusion Protocol (MTP)

The indications for activation of Massive Transfusion Protocol (MTP) include:

• Severe traumatic bleeding, as evidenced by the need for rapid transfusion of blood products 2, 3, 4
• Postpartum hemorrhage (PPH), which is a leading cause of maternal death worldwide 5, 6
• Obstetrical hemorrhage, including uterine atony and placenta accreta spectrum 5
• Trauma-induced coagulopathy, which requires early diagnosis and treatment with blood products and other therapies 2

Key Factors in MTP Activation

Key factors in MTP activation include:

• Estimated blood loss, with higher volumes indicating a greater need for transfusion 5, 6
• Clinical response to initial transfusion, with ongoing bleeding or hemodynamic instability indicating the need for continued transfusion 5
• Laboratory findings, including hematologic and clotting parameters, which can guide the use of blood products and other therapies 5, 2, 6
• The use of scoring systems to detect patients with severe post-traumatic bleeding, which can help identify those who may benefit from MTP activation 4

Blood Product Transfusion Ratios

The optimal ratios of blood products to be transfused in MTP are:

• 1:1:1 to 1:1:2 ratios of plasma, platelets, and red blood cells, as recommended by current guidelines 2, 3
• Individualized approaches to transfusion, based on the etiology of the hemorrhage and the patient's response to initial therapy 5, 2